definitions Flashcards
copies the genetic instructions from DNA in the nucleus, and carries the instructions to the cytoplasm.
mRNA
Helps form ribosomes, the organelle where proteins are assembled.
rRNA
Brings amino acids to ribosome, where they are joined together to form proteins.
tRNA
The addition of nucleotides to the growing mRNA strand.
Elongation
The beginning of transcription occurs when mRNA polymerase binds to the promoter of a gene
Initiation
Ending of transcription and occurs when RNA polymerase crosses as stop sequence in the gene.
Termination
Group of three nitrogen bases in RNA or DNA that is the genetic code word for a single amino acid or for a star or stop signal
Codons
The three-base frame that divides the base into codon
Reading frame
Structure found in all cells that is the site of protein synthesis
Ribosome
Nonliving aspect of the enviroment such as sunlight and water
Abiotic factors
Are the living aspects of the environment. They consist of other organisms, including members of the same and different species.
Biotic factors
Two species within the same area coexist and adapt by developing different specializations
Character displacement
Is a relationship between two species, or individuals of the same species that strive the same resources in the same place
Competition
Is an organism that must eat or consume other organisms to optain energy and nutrients.
Consumer
Branch of biology that is the study of how living things interact with each other and with their environment
Ecology
Role that a particular species plays in the ecosystem, including all the ways that the species interacts with the biotic and abiotic factors in the ecosystem
Niche
All the organisms of the same species that live in the same area
Population
Type of organism that uses light energy or chemical energy to make food for itself and others.
Producers
Aquatic biome such as pond, lake, stream or river in which the water contains little or no salt.
Freshwater biome
Predator species that plays a special role in its community because changes in its population affect the populations of many other species in the community
Keystone species
Interaction between two organisms of unlike species: one organism acts as predator that captures and feeds on the other organism wich is the prey
Predator-prey relationship
A situation in which a species completely dies out and no members remain
Extinction
The relationship between organisms between different species that strive for the same resources in the same place
Interspecific relationship
The relationship between organism of the same species that strive for the same resources in the same place
Intrapecific relationship
Close relationship between two species in which at least one specie benefits
Symbiosis
Type of species that first colonized a disturbed area
Pioneer species
Change in the numbers and types of species that live in a community that occurs in an area that has never before been colonized by organisms and lacks soil.
Primary succession
Change in the numbers and types of species that live in a community that occurs in an area that has soil and was previously colonized but has been disturbed
Secondary succession
Bar graph that represents the number of individuals of each sex and age in a population
Population pyramid
Movement of individuals out of a population
Emigration
Movement of individuals into a population
Immigration
Regular movement of individuals or population each year during certain seasons, usually to find food, mates or resources
Migration
Organism that makes its own food
Autotrophs
Type of organism that obtains food by breaking down the remains of dead organisms or other organic wastes into its various organic wastes into its various components including nutrients that can be used by other organisms
Decomposers
Organism that can get food by consuming other organism
Heterotrophs
Type of decomposer that consume dead animals.
Scavengers
All the living things in a given area together with the physical and chemical factors of the nonliving enviroment
Ecosystem
Total mass of organisms at a given trophic level in a food chain or web.
Biomass
An organism’s feeding position in a food chain
Trophic level
The evaporation that occurs from the land surface along with transpiration
Evapotranspiration
Release of water vapor into the atmosphere from stomata in the leaves of plants
Transpiration
Process of changing nitrogen gas to nitrates that is carried out by nitrogen fixing bacteria in the soil or the roots of legumes
Nitrogen fixation
Variety of life within a particular habitat, often measured by the number of different species.
Biodiversity
An area with similar climate that includes similar communities of plants and animals
biome
Average weather in an area over a long period of time
Climate
Group of similar land based ecosystem such as tropical rainforests temperate grasslands of tundras
Terrestrial biomes
Area in a body of water that is deeper than 200m where sunlight doesn’t penetrate to allow photosynthesis to take place
Aphotic zone
Water based biome or group of similar water based ecosystems includes freshwater or marine biomes
Aquatic biomes
Aquatic biome in the salt water of the ocean.
Marine biomes
Area in a body of water that extends to a maximum depth of 200m and where enough sunlight penetrates to allow photysnthesis to take place
Photic zones
Largest population size of a species that can be supported by the environment
Carryinc Capacity
Monomer of a protein
Amino acids
Individuals that dont have the genetic disorder themselves but they carry the mutant allele that can pass to their offspring
Carriers
dna to rna to ptotein
central dogma of molecular biology
observations by Chargaff that concentrations of the four nucleotide bases differ over species a=t c+g
Chargaff’s rules
Relationship between two alleles for the same gene in which both alleles are expressed equally in the phenotype of the heteroygote
Codominance
Double-stranded nucleic acid that stores genetic information also known as deoxyribonucleic acid
DNA
Double spiral shape of the DNA molecule
Double helix
Universal code of the three-base codons that encodes the genetic information for the amino acid sequence of protein
Genetic code
All of the hereditary information encoded in the DNA of the species
Genome
Organims that inherits two different alleles for a given gene aka heterozygous
Heterozygote
International science project that sequenced all 3 billion base pairs of the human genome
Human genome project
Relatiobnship between the alleles for a gene in which one alleles is only partly dominant to the other allele so an intermediate phenotype results
Incomplete dominance
A change in the sequence of bases in DNA
Mutations
Organic compounds such as DNA and RNA that is made of monomers called nucleotides
Nucleic acid
Monomer of nucleic acids 5 carbon sugar, phosphate group and nitrogen base
Nucleotide
Characteristic or trait controlled by more than one gene each of which may have two ore more alleles
Polygenic traits
Process in which cells make proteins includes transcription (DNA to mRNA) and translation (mRNA to protein)
Protein synthesis
Single stranded nucleic acid that helps make proteins
RNA
Process in which genetic information in DNA are copied to form a complementary strand of mRNA
Transcription
Containing a gene transferred from another organism
Transgenic
Process in which the genetic code in mRNA is rode, one at the time, to make protein
Translation
Traits controlled by a gene located in the X chromosomes
X-linked traits
Energy-requiring movement of molecules across a membrane from a region of lower concentration to one of higher concentration
Active transport
Any of the alternative forms of a gene that occurs at a specific place on a chromosome
Allele
High energy moleculoe that contains energy that cells can use
ATP
Basic unit of life
Cell
Double-layer of phospholipids that forms a boundary between the cell and the sorrounding enviroment and controls the passage of materials into and out of the cell
Cell membrane
Process of producing ATP by breaking down carbon-based molecules when oxygen is present
Cellular respiration
Organelle composed of numerous membranes that are used to convert solar energy into chemical energy contains chrolophyll
Chloroplast
Long, continuous thread of DNA that consists of numerous genes and regulatory information
Chromosome
Cell that has two copies of each chromosonme one from the egg and one from the sperm
Diploid
Allele that is expressed when two different alleles are present in a organism’s genotype
Dominant
Interconnected network of thinm, folded membranes that produce, process, and distributes proteinbs
ER
Protein that catalyzes chemical reactions for organisms
Enzyme
Sex cell eg or sperm
Gamete
Specific region of DNA that codes for a particular protein
Gene
Cell that has only one copy of the chromosome
Haploid
Regulation and maintenance of constant internal conditions in a organism
Homeostasis
Proposed explanation or answer to a scientific question
Hypothesis
Form of nuclear division that divides a diploid cell into a haploid cell important in forming gametes for sexual reproduction
Meiosis
Bean shaped organelle that supplies energy to the cell and has its owns ribosomes and dna
Mitochondria
process by which a cell divides nucleous and organelles
Mitosis
Molecular subunit of a polymer
Monomer
Organelle composed of a double membrane that stores DNA
Nucleus
Any individual living thing
Organism
Measurement of acidity
pH
Process in which light energy is converted into chemical energy produce sugar and oxygen from water and carbon dioxide
photosynthesis
Larger carbon based molecules formed by monomers
Polymer
Model for predecting all posible genotypes resulting from a cross or mating
Punnet square
Allele that is not expressed unless two copies are present in a organism’s genotype
Recessive
Conditions or qualify of allowing some but not all materials to cross a barrier or membrane
Selective permebility
Group or organisms so similar to one another that they can breed and produce a fertile offspring
Species